Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_...Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.展开更多
The global consumption of p-xylene(PX)for the production of polymers has raised serious concerns about its impact on the environment.As various reports have shown the risks that PX could pose to human health,research ...The global consumption of p-xylene(PX)for the production of polymers has raised serious concerns about its impact on the environment.As various reports have shown the risks that PX could pose to human health,research into cost-effective remedial methods to remove PX from the environment has gained attraction.In this work,a hierarchical porous crab shell biochar(KCS)was synthesized,characterized,and evaluated for its efficiency to remove PX from aqueous solution.The characterizations of KCS,including the porous structure,surface functional group,phase structure,and surface morphology,were discussed by N_(2) adsorption-desorption,FTIR,XRD,and SEM.Batch adsorption experiments showed that the maximum adsorption capacity of PX on KCS was 393 mg/g within 5 min,larger than most biological/biomass materials,mainly due to the higher specific surface area of 2046 m^(2)/g,and abundant lipophilic functional groups.Subsequent adsorption kinetics study indicated a pseudo-second-order model which implied that the adsorption of PX was due to chemisorption.Thermodynamic parameters showed that the values ofΔH°andΔG°were both negative,indicating that the PX adsorption process on KCS was spontaneous and exothermic.The performance of KCS in delivering a cost-effective,fast,and efficient solution for the removal of PX from aqueous solution would greatly benefit current environmental remediation efforts.展开更多
In this study,a porous biochar material derived from waste crab shell was prepared by one-step hydrothermal carbonization and acetic acid activation method at 180°C,which was characterized by SEM,BET,XRD and FTIR...In this study,a porous biochar material derived from waste crab shell was prepared by one-step hydrothermal carbonization and acetic acid activation method at 180°C,which was characterized by SEM,BET,XRD and FTIR.The results show that the as-prepared crab shell biochar(CSB)exhibits a fluffy irregular layered structure with abundant pores and oxygen-containing functional groups,which can facilitate the adsorption of diesel using CSB.In addition,batch adsorption experiments had been performed,effects of initial diesel concentration,adsorption time,adsorbent dosage and pH on the diesel adsorption using CSB were analyzed,which could be observed that CSB has high removal efficiency for diesel,and the maximum removal rate is up to 80.1%.The adsorption isotherms and kinetic studies were also investigated to determine the adsorption mechanism of diesel using CSB,the results show that the Langmuir model and the pseudo-second-order model are more suitable for describing the adsorption of diesel using CSB,indicating that the adsorption of diesel oil by CSB is monolayer chemical adsorption.This study will provide a theoretical basis for the high-value utilization of waste crab shell,which has a great potential in the treatment of oil spill.展开更多
Crab shells are an important feedstock for chitin production.However,their highly compact structure significantly limits their use for the production of chitin under mild conditions.Here,a green and efficient approach...Crab shells are an important feedstock for chitin production.However,their highly compact structure significantly limits their use for the production of chitin under mild conditions.Here,a green and efficient approach using a natural deep eutectic solvent(NADES)to produce chitin from crab shells was developed.Its effectiveness in isolating chitin was investigated.The results showed that most proteins and minerals were removed from crab shells and the relative crystallinity of the isolated chitin reached 76%.The quality of the obtained chitin was comparable to chitin isolated by the acid–alkali method.This is the first report on a green method for efficient chitin production from crab shells.This study is expected to open new avenues for green and efficient production of chitin from crab shells.展开更多
Biomass-based carbon materials with hierarchical porous structures have attracted attention for their ability to provide more channels and shorten ion transport paths.Here,we developed a simple method based on confine...Biomass-based carbon materials with hierarchical porous structures have attracted attention for their ability to provide more channels and shorten ion transport paths.Here,we developed a simple method based on confined nanospace deposition.Dur-ing high-temperature treatment,the mesoporous silica layer wrapped around the outside of the crab shells acted as a closed nanospace and effectively suppressed the severe deformation of the crab shell structure by shrinking inward.The prepared carbon material has a layered porous structure with abundant and stable N and O co-doping(N 7.32%,O 3.69%).The specific capacitance of the three-electrode system was 134.3 F/g at a current density of 0.5 A/g in a 6 mol/L KOH electrolyte,and the assembled aqueous symmetric supercapacitors exhibited an excellent cycling stability of 98.81%even after 5000 cycles.展开更多
基金funded the World Class Research(WCR)Grant of Universitas Diponegoro with Contract Number 357-36/UN7.D2/PP/IV/2024.
文摘Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.
基金supported by the Natural Science Foundation of Zhejiang Province of China(No.LQ16D060004)Key Research and Development Projects of Zhejiang Province of China(No.2018C02043)+1 种基金Demonstration Project of Marine Economic Innovation and Development of Zhoushan City of ChinaDemonstration Project of Marine Economic Innovation and Development of Yantai City of China(No.YHCX-SW-L-201705).
文摘The global consumption of p-xylene(PX)for the production of polymers has raised serious concerns about its impact on the environment.As various reports have shown the risks that PX could pose to human health,research into cost-effective remedial methods to remove PX from the environment has gained attraction.In this work,a hierarchical porous crab shell biochar(KCS)was synthesized,characterized,and evaluated for its efficiency to remove PX from aqueous solution.The characterizations of KCS,including the porous structure,surface functional group,phase structure,and surface morphology,were discussed by N_(2) adsorption-desorption,FTIR,XRD,and SEM.Batch adsorption experiments showed that the maximum adsorption capacity of PX on KCS was 393 mg/g within 5 min,larger than most biological/biomass materials,mainly due to the higher specific surface area of 2046 m^(2)/g,and abundant lipophilic functional groups.Subsequent adsorption kinetics study indicated a pseudo-second-order model which implied that the adsorption of PX was due to chemisorption.Thermodynamic parameters showed that the values ofΔH°andΔG°were both negative,indicating that the PX adsorption process on KCS was spontaneous and exothermic.The performance of KCS in delivering a cost-effective,fast,and efficient solution for the removal of PX from aqueous solution would greatly benefit current environmental remediation efforts.
基金This study was supported by the Fundamental Research Funds for Zhejiang Provincial Universities and Research Institutes(Nos.2019J00045,2019J00025)the General Research Project of Zhejiang Province Education Department(No.Y202044721)Key Research and Development Projects of Zhejiang Province of China(No.2018C02043).
文摘In this study,a porous biochar material derived from waste crab shell was prepared by one-step hydrothermal carbonization and acetic acid activation method at 180°C,which was characterized by SEM,BET,XRD and FTIR.The results show that the as-prepared crab shell biochar(CSB)exhibits a fluffy irregular layered structure with abundant pores and oxygen-containing functional groups,which can facilitate the adsorption of diesel using CSB.In addition,batch adsorption experiments had been performed,effects of initial diesel concentration,adsorption time,adsorbent dosage and pH on the diesel adsorption using CSB were analyzed,which could be observed that CSB has high removal efficiency for diesel,and the maximum removal rate is up to 80.1%.The adsorption isotherms and kinetic studies were also investigated to determine the adsorption mechanism of diesel using CSB,the results show that the Langmuir model and the pseudo-second-order model are more suitable for describing the adsorption of diesel using CSB,indicating that the adsorption of diesel oil by CSB is monolayer chemical adsorption.This study will provide a theoretical basis for the high-value utilization of waste crab shell,which has a great potential in the treatment of oil spill.
基金supported by China Agriculture Research System(CARS-48)Taishan Scholar Project of Shandong Province(tsqn201812020)Fundamental Research Funds for the Central Universities(201941002).
文摘Crab shells are an important feedstock for chitin production.However,their highly compact structure significantly limits their use for the production of chitin under mild conditions.Here,a green and efficient approach using a natural deep eutectic solvent(NADES)to produce chitin from crab shells was developed.Its effectiveness in isolating chitin was investigated.The results showed that most proteins and minerals were removed from crab shells and the relative crystallinity of the isolated chitin reached 76%.The quality of the obtained chitin was comparable to chitin isolated by the acid–alkali method.This is the first report on a green method for efficient chitin production from crab shells.This study is expected to open new avenues for green and efficient production of chitin from crab shells.
基金China Postdoctoral Science Foundation,2023M732589,Zhihao YuNational Natural Science Foundation of China,22308253,Zhihao Yu,51908400,Rui Zhang,52066017,Xuebin Lu+2 种基金Central Financial Support Special Funds for Local Universities(Tibet University),[2022]No.1,Xuebin Lu,[2023]No.1,Xuebin LuTibet University Postgraduate High Level Talent Training Programme,2020-GSP-B017,Xuebin LuKey R&D Projects in Tibet Autonomous Region,XZ202101ZY0011G,Xuebin Lu,XZ202101ZY0012G,Xuebin Lu.
文摘Biomass-based carbon materials with hierarchical porous structures have attracted attention for their ability to provide more channels and shorten ion transport paths.Here,we developed a simple method based on confined nanospace deposition.Dur-ing high-temperature treatment,the mesoporous silica layer wrapped around the outside of the crab shells acted as a closed nanospace and effectively suppressed the severe deformation of the crab shell structure by shrinking inward.The prepared carbon material has a layered porous structure with abundant and stable N and O co-doping(N 7.32%,O 3.69%).The specific capacitance of the three-electrode system was 134.3 F/g at a current density of 0.5 A/g in a 6 mol/L KOH electrolyte,and the assembled aqueous symmetric supercapacitors exhibited an excellent cycling stability of 98.81%even after 5000 cycles.
